<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>登录</title>
</head>
<body>

<form action="login">
    用户 <input type="text" name="username" placeholder="请输入用户名"> <br>
    密码 <input type="password" name="password" placeholder="请输入密码"> <br>
    <input type="image" src="checkCode">
    验证码：<input type="text" name="checkCode">
    <input type="submit">
</form>
</body>
</html>